The present invention relates to multiplying a digital signal by a coefficient, and more particularly to such multiplying as occurs in a matrix for video signals.
In television studio equipment it is frequently desired to generate Y (luminance) and I & Q (chroma) signals from R (red), G (green) and B (blue) signals in accordance with the following matrix equation: ##EQU1## Typical prior approaches use either ROMs (read only memories) to perform the multiplication or shifting and adders to perform the multiplication. In particular for the approach using ROMs to perform the multiplication, each of the three channels to generate the Y, I, and Q signals would comprise about 3 ROMs, 2 adders, and 6 latches, for a total of about 33 ICs (integrated circuits) for all 3 channels. Such a number of ICs is relatively expensive and consumes a large amount of power. Also the approach using shifting and adding to perform the multiplication requires a large number of ICs to achieve the desired accuracy.
It is therefore desirable to provide a digital multiplier, such as a matrix, that requires a minimum number of components and power.